A semiconductor device is a substrate inserted lead-type semiconductor device to be mounted through insertion of a plurality of lead terminals into a plurality of respective through holes of a substrate. The semiconductor device includes: an energization controller including a semiconductor element and wiring; a sealing resin to cover the energization controller; and the lead terminals each having one end side connected to the energization controller and the other end side protruding from the sealing resin. The lead terminals each have a protrusion formed on a part of the other end side protruding from the sealing resin.